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The "HadoopIsNot" page has been changed by SteveLoughran:
http://wiki.apache.org/hadoop/HadoopIsNot?action=diff&rev1=7&rev2=8
== Hadoop is not an ideal place to learn networking error messages ==
- You will find things work a lot easier if you are already familiar with networking and the
common error messages -for example, what [[ConnectionRefused| "Connection Refused"]] means,
and how is different from "No Route to Host".
+ You will find things work a lot easier if you are already familiar with networking and the
common error messages -for example, what [[ConnectionRefused| "Connection Refused"]] means,
and how is different from [[NoRouteToHost| "No Route to Host"]].
- A lot of people post onto the user list with problems related to [[ConnectionRefused| "Connection
Refused"]], [[NoRouteNoHost| "No Route to Host"]] and other common TCP-IP level errors. These
are usually signs of an invalid cluster configuration, some parts of the cluster not running,
or machines not being able to talk to each other on the LAN. People on the mailing list cannot
debug your network configuration for you, as it is your network, not theirs. They can point
you at some of the tools and tests to try, but since it will take a day for every email round
trip, you won't find this a very fast way to get help.
+ A lot of people post onto the user list with problems related to [[ConnectionRefused| "Connection
Refused"]], [[NoRouteToHost| "No Route to Host"]] and other common TCP-IP level errors. These
are usually signs of an invalid cluster configuration, some parts of the cluster not running,
or machines not being able to talk to each other on the LAN. People on the mailing list cannot
debug your network configuration for you, as it is your network, not theirs. They can point
you at some of the tools and tests to try, but since it will take a day for every email round
trip, you won't find this a very fast way to get help.
Nobody in the Hadoop team are deliberately trying to make things hard, its just that when
things do not work in a large distributed system, you get some interesting error messages.
If you can help improve those network messages or diagnostics, we would love to have that
code.